Mad Men’s Christina Hendricks is praised for her buxom figure – as well as her acting talent, although science say she’s too big to be the ‘ideal’ size

That’s the conclusion of a team of scientists led by Jan Havlíček, from the Faculty of Science, at Prague’s Charles University, Czech Republic.

They wanted to see what appeals to men the most in order to successfully breed.

And the ever-changing shape of breasts, or morphology, keeps men interested.

The team wrote: “The morphology of human female breasts appears to be unique among primates due to their permanent fat deposits.

“It has been previously suggested that female breast morphology arose as a result of sexual selection. “This is supported by evidence showing that women with larger breasts tend to have higher estrogen levels; breast size may therefore serve as an indicator of potential fertility.

“However, breasts become less firm with age and parity, and breast shape could thus also serve as a marker of residual fertility.”

And that seems to be the driving force in men, the scientists found.

They arrived at their conclusions after showing a variety of boob pictures to 247 blokes who then rated them on what they fancied the most.

The study says men are hypothesised to prefer breast morphology that indicates “both high potential and residual fertility”

The team said of their study published in the journal Evolution and Human Behaviour: “Cross-culturally, males are hypothesised to prefer breast morphology that indicates both high potential and residual fertility.

“To test this, we performed a survey on men’s preferences for breast morphology in four different cultures, Brazil, Cameroon, the Czech Republic, Namibia.
“As stimuli, we used two sets of images varying in breast size (marker of potential fertility) and level of breast firmness (marker of residual fertility).

Cross-culturally, males are hypothesised to prefer breast morphology that indicates both high potential and residual fertility

Jan Havlíček, Prague's Charles University

“Individual preferences for breast size were variable, but the majority of raters preferred medium sized, followed by large sized breasts.

“In contrast, we found systematic directional preferences for firm breasts across all four samples.

“This pattern supports the idea that breast morphology may serve as a residual fertility indicator, but offers more limited support for the potential fertility indicator hypothesis.

“Future studies should focus on a potential interaction between the two parameters, breast size and firmness, which, taken together, may help to explain the relatively large variation in women’s breast sizes.”

The majority of men studied preferred medium sized, followed by large sized breasts – as often displayed by Kate Upton

This latest study into men’s fascination with breasts comes just three months after scientists developed a theory for the chest’s hypnotic appeal.

According to boffins who’ve studied our love of boobs, there are two main reasons – the first being that they look a bit like bottoms.

And for good reason, according to evolutionary scientists.

The theory goes that, as the female hormone oestrogen leads to fat storage in the hip and bottom area, women originally developed round buttocks to show potential mates how fertile they were.

Biological anthropologist Bobbi S. Low has stated that rounded rears “evolved in the context of females competing for the attention and parental commitment of powerful resource-controlling males” as an “honest display of fat reserves”.

Sexologist Alfred Kind pointed out that primates, including early man, did not initially face each other while having sex and therefore the bottom is the “primary sexual presentation site in primates”.

BREAKFAST CLUB

Men from Brazil, Cameroon, the Czech Republic and Namibia all willingly contributed to the research

Anthropologists believe our love of boobs stems from their similarity to the buttocks and that they became more sexually attractive when human beings started having sex face-to-face.

Meanwhile, the second reason is less surprising – it’s all about the breastfeeding.

When a baby is suckled by mum, the hormone oxytocin is released and the result is an overwhelming feeling of love and bonding.

The same hormone is released when breasts are stimulated during sex, bringing on a sense of pleasure and closeness.

Nursing also brings a feeling of deep relaxation and contentment.

According to neuroscientists and Brian Alexander, authors of The Chemistry Between Us: Love, Sex, and the Science of Attraction, adult men’s love of boobs harks back to subconscious memories of the effect of manipulating their mother’s breast to release oxytocin.